Abstract: Pt/SrBi₂Ta₂O₉/Bi₄Ti₃O₁₂/p-Si heterostructures were fabricated by sol-gel method. The effects of annealing temperature on microstructure, crystal growth behavior, leakage current density, and C-V characteristics of Pt/SrBi₂Ta₂O₉/Bi₄Ti₃O₁₂/p-Si heterostructure were investigated. The SrBi₂Ta₂O₉/Bi₄Ti₃O₁₂ multilayer thin films annealed at low temperature are polycrystalline, and grow in the preferred c-axis orientation with the increase of annealing temperature. The C-V curves of Pt/SrBi₂Ta₂O₉/Bi₄Ti₃O₁₂/p-Si heterostructure annealed at various temperatures all show a clockwise ferroelectric hysteresis loop. The widths of C-V hysteresis loops of Pt/SrBi₂Ta₂O₉/Bi₄Ti₃O₁₂/p-Si heterostructure increase with the increase of annealing temperature and reach a maximum of 0.78V when the heterostructure is annealed at 700℃. The leakage current density of Pt/SrBi₂Ta₂O₉/Bi₄Ti₃O₁₂/p-Si heterostructure decrease slowly with the increase of annealing temperature from 550℃ to 650℃. However, when the annealing temperature is above 650℃, the leakage current density of Pt/SrBi₂Ta₂O₉/Bi₄Ti₃O₁₂/p-Si heterostructure increase evidently. The lowest leakage current density is 2.54×10^-7A/cm² when Pt/SrBi₂Ta₂O₉/Bi₄Ti₃O₁₂/p-Si heterostructure is annealed at 650℃.

Key words: annealing temperature, SrBi₂Ta₂O_9, Bi₄Ti₃O₁₂, heterostructure